Rail bond terminal



y 20, 1952 H. J. BROWN ET AL 2,597,444

RAIL BOND TERMINAL Filed Jan. 21, 1948 CD 3 6 Q f I lgJNVENTORS BY 9"LOW Patented May 20, 1952 RAIL BOND TERMINAL Harold J. Brown, Johnstown,Pa., and Frederick C. Lavarack, Montclair, N. J said Lavarack assignorto Railroad Accessories Corporation, New York, N. Y., a corporation ofNew York Application January 21, 1948, Serial No. 3,513 1 Claim. (01.2s7-20.3

This invention relates to electrical connectors,

ing continuity between the ends of railway rails which are commonlyknown as rail bonds.

A principal object of this invention is the production of a rail bondterminal adapted to be secured in a cavity in the side of a rail headwhich will be effectively and tightly compressed against the surface ofthe cavity in the rail head right at the juncture of that surface withthe outside surface of the side of the rail head.

Another object of the invention is to produce a terminal of the typespecified which is independent of depth of the cavity formed in the railhead, provided that cavity is at least a minimum depth.

Another object of the invention is to produce a bond terminal of thetype specified which will present visible evidence of the completion ofthe driving effort used in securing the bond in the rail head cavity.

Other objects and advantages will appear as the description of theparticular physical emfor insertion in cavities in the several railheads and an electrically conducting cable, such as 3, connecting theparts secured in the cavities.

Rail head bonds are in common use, of the type having terminals securedin cavities formed in the side face of the rail head. The cavities areformed in the side face of the rail head by drilling. The drill issupposed to penetrate into the rail a predetermined distance formingwhat might be called a blind hole. Due to, perhaps, lack of properadjustment or carelessness, the hole may well depart from standarddepth. It

may either be deeper or shallower. In spite of all bodiment selected toillustrate the invention progresses and the novel features will beparticularly pointed out in the appended claim.

In describing the invention in detail and the particular physicalembodiment selected to illustrate the invention, reference will be hadto the accompanying drawings and the several views thereon, in whichlike characters of reference designate like parts throughout the several views, and in which:

Fig. 1 is a fragmentary side elevational view of the adjacent ends oftwo railway track rails with a bond of our invention in place thereon;Fig. 2 is a top plan view of the device as shown by Fig. 1; Fig. 3 is asectional view of the device as shown by Fig. 1 on the plane indicatedby the line IIIIII viewed in the direction of the arrows at the ends ofthe line; Fig. 4 is a view similar to Fig. 3 but showing the starting ofan expanding pin used with our invention; Fig. 5 is a View similar toFig. 3 and Fig. 4 but showing a further advance of an expanding pin usedwith our invention.

In Fig. 1, l designates one rail and 2 designates the other rail of twoabutting railway rails such as are commonly used as the track upon whichrailway cars travel.

3 designates, as a whole, what is known as a head of rail railway bond.This device is used to electrically connect the end of one abutting railwith the end of the other abutting rail, and generally includes solid orhollow studs the care taken, the hole may also be out of round and notalways the same diameter; The result is that the cavity is not alwaysproper in depth, roundness and diameter in which to properly aiiix theterminal where the bottom of the hole or cavity is used as what might becalled an anvil to assist in securing the terminal in the cavity. Incase the bottom of the hole is used as an anvil, and the hole isshallow, a poor electrical and mechanical connection is made with theterminal and the terminal protrudes from the side face of the rail morethan it should so that there is added danger that dragging rolling stockequipment may contact with and shear off the terminal. If the hole is oftoo great depth, there is danger that when the terminal is afilxed inthe rail, the head thereof may be considerably weakened and perhapssheared off by contacting with the side face of the rail before the endof the terminal contacts with the bottom of the cavity. The difficultiespointed out arise mainly from the fact that the bottom wall of thecavity is used as an anvil in securing the terminal in the cavity.

.We propose to obviate the difiiculties hereinbefore mentioned andoccurring by reason of the use of the bottom or end wall of the cavityin the rail head as an anvil by producing a bond which may be properlysecured in a blind hole or cavity without utilizing the bottom or endwall thereof.

Our type of bond terminal is secured in a cavity in the side of the railhead, as d, which is preferably made of standard diameter and standarddepth in accordance with the specifications of the American RailwayAssociation.

Our type of bond includes a stud 5 which is cylindrical and ha anoutside diameter perhaps just slightly less than that of the diameter ofthe standard cavity 4 so that it may be slipped into place. The stud 5is integrally attached to a body 6. The body 6 is formed with an annulargroove 1, one side of which is formed by the outside surface of the stud5. This construction provides a stud 5 which, in effect, extends for aslight distance outside of the cavity 4.

In order to properly position the stud 5 endwise in the cavity 4, weprovide a surface 8 on the body 6 which just contacts the side faceof arail, as 2, when the stud 5 has beenintroduced the proper distance intothe cavity 4. This proper distance of introduction positions the stud 5so that its inner end is free from contact with the bottom or end wall 9of the cavity 4.

The stud 5 and the body 6 are formed with axially aligned through bores,as ID, in the stud 5, and II in the body 6. are not of the samediameter. The bore in body 6 is of a larger diameter than the bore instud ID.

The bore in body -8 is preferably of an internal diameter just slightlyless than the external diameter of the expanding pin l2 so that theexpanding pin may be inserted in the body 6 and pushed to the positionsas shown in Fig. 5 by a slight force. This would serve to maintain thepin in place while being shipped. This construction obviates anysubstantial expansion of the body 6 by the insertion of expanding pin I2therein.

The bore 10 is made of such diameter relative to the outside diameter ofexpanding pin l2, that when expanding pin I2 is driven therein it willproperly expand the walls left around the bore l0 against the insidesurface of the cavity 4 so asto securely and properly maintain theterminal in place.

A- difliculty which has been met with many bonds of the prior art isthat the stud of the bond did not so securely and tightly compressagainst the inside surface of the cavity 4 about the corner l3 as toproperly exclude moisture from working therein between the stud and thesurface of the cavity. In our form of bond we, in effect, extend thestud outside of the cavity. We do this by formin the groove I in the:body 6. When the pin [2 is driven into the stud 5, expansion startsabout in the plane of the line [4, so that at the plane of the face ofthe rail full expansion is obtained so as to force the outside surfaceof the stud 5 into firm and moisture excluding contact with the insidesurface of the cavity 4, especially adjacent the edge or corner [3 wheremoisture is most likely to secure an entrance. In our construction assoon as the expansion pin reaches the position as shown in Fig. 5 andthe driving is started, expansion of the stud starts. This expansion ofthe stud is of that part which is really outside of the cavity so thatas the expansion pin is driven further in it is certain that expansionis started right at the juncture between the inside surface of thecavity and the outside surface of the face of the rail. This expansionis particularly efficient because of the presence of the annular grooveI which allows expansion of the metal to take place rather than merecompression. In the absence of the annular groove 1, when the expansionpin is driven, due to the large body of material existing outside of thecavity, compression of that material rather than expansion would be themajor effect. Our construction enables us to obtain substantiallyuniform expansion the full length of the stud, that is, that part whichis within the cavity and that portion which is without the cavity.

Figure 4 illustrates the pin l 2 as being inserted in the bore ll almostto the point where it is to These bores, however, 7.

contact the walls of the reduced here. Fig. 5 shows the pin I2 inposition where it must be given considerable force to be advanced towardthe end wall 9 of the cavity 4. Fig. 3 shows the pin l2 completelydriven to its final position.

It will be noted that when pin 12 is flush with the outside face I! ofthe body 6 a visible indication is afforded that the driving effort hasbeen completed and that th best possible mechanical and electricalconnection ha been made between the stud 5 and the cavity in the railhead. When the pin has thus been driven it is noted that the inner endhas been driven completely through the stud andthat the pin has bothexpanded the stud-and compressed the metal thereby toughening andstrengthening the metal and pressing it firmly against the inner surfaceof the cavity throughout the entire length of the stud. This visibleindication of the completion of the attachment obviates the likelihoodeither that there will be over driving or under driving of the pin.

In the particular form of body shown we have included a cavity l5 intowhich the metallic cable or conductor 3 may be inserted and secured forthe purpose of interconnecting terminals of adjacent rail heads.

The several figures also show the body 6 formed with a sloping surfacel6 for intercepting and warding off dragging equipment which mightinjure the bond.

It is to be understood that the particular method and means forinterconnecting one bond terminal to another and the presence or absenceof means for guarding the central portion of the body 6 are merely shownfor completeness, but neither one of these features in its specific formis essential to our invention.

From the hereinbefore given description it will be'apparent that ourform of bond terminal is most eflicient in securing a moisture proof andstrong type mechanical connection in the plane of the edge l3, that is,in the plane of the side face of the rail at the juncture thereof withthe inside surface of the cavity. It will also be noted that variationsin the depth of the cavity 4 are immaterial to the proper use of ourterminal, provided that at least a minimum depth is provided. It shouldalso be noted that in prior art structures where the bottom of the holeis used as an anvil, there is no proper indication of the necessarystrength of hammer blow to be given to the terminal in order to secure auniform tightening of all terminals in the cavity in the rail head,whereas in our type the visual indication given by the flush position ofthe outer end of the expanding pin to the face of the body of the bondis an assurance not only of the necessary strength of hammer blow, butof a uniformity of tightening of the stud in the cavity of the railhead. It should further be noted that with our type of rail terminal wevirtually measure the depth of the hole because if the stud does not gointo the cavity in the rail head so that the body rests squarely againstthe side face of the rail head before any blows are given to theexpansion pin, the hole is not of the proper minimum depth. On the otherhand if the hole is slightly too deep, no difficulty is caused, whereasin prior forms of bond which employed the bottom of the hole or cavityas an anvil, if the hole were too deep either the head or body would beinjured or difficulty would be encountered in extracting the pin fter ithad been secured in the hole and at a later time it was found necessaryto take it out.

Although we have particularly described several particular physicalembodiments of our invention and explained the operation, constructionand principle thereof, nevertheless we desire to have it understood thatthe forms selected are merely illustrative, but do not exhaust thepossible physical embodiments of the idea of means underlying ourinvention.

' What we claim as new and desire to secure by Letters Patent is:

A rail bond terminal for aflixing in a rail cavity of predetermineduniform diameter throughout and of a predetermined depth and formed witha conical end wall, said termina1 formed of one piece comprising a bodyand a cylindrical stud, the cylindrical stud portion for insertion in arail cavity, said body formed with a fiat portion abuttable against arail, said. termina1 further formed with an annular groove surroundingthe stud whereby the stud is free from the body for the depth of thegroove, said body and stud formed with a through aligned bore, said borebeing of one diameter in the body of the terminal and of a less butuniform diameter through the stud,

an expanding pin of the same diameter as and positioned in the bore ofthe body ands'aid body formed with a portion for attachment of anelectrical conductor.

HAROLD J. BROWN. FREDERICK C. LAVARACK.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name v Date 582,849 Daniels May 18, 1897587,134 Mosher July 2'7, 1897 601,707 Dainton Apr. 5', 1898 666,403 WoodJan. 22, 1901 752,034 Clifi Feb. 16, 1904 1,615,187 Bossert et al. Jan.18, 1927 2,135,888 Febrey Nov. 8, 1938 2,232,999 Chandler Feb. 25, 19412,248,845 Beam July 8, 1941 2,259,368 Febrey Oct. 14, 1941 Sabol May 12,1942

